Andrew Gabriel wrote:
In article ,
"Toby" writes:

Surely a 15W lamp is going to be running at the same temperature as any
other filament lamp at the same voltage?

No, there's a range of temperatures filament lamps operate over.

If the "special appliance" lamp is also 15w, but produces less light, it
would throw out even more heat!?

A 15W mains filament lamp is so inefficient, that you can regard it
as generating 100% heat to a first approximation.

Surely, regardless of how efficient or otherwise it is at producing
light, the light ends up as heat anyway. So given a 15 watt lamp
*all* of the 15 watts ends up heating the room that the lamp is in
except for any light that escapes the room.

--
Chris Green